Evaluation of Entropy Driven Compression Bounds on Industrial Designs

The use of scan based compression techniques is becoming mandatory on current designs. While high compression is desired to hold the test costs within limits, it is important to understand the bounds set by the entropy of the care bits required by different compression techniques, to enable the selection of the right set of design and test parameters. This paper highlights the available solution space for compression based designs and discusses the various parameters which result in test tradeoffs. The discussion is supported with elaborate experimental data. Through them, the paper offers an insight into the solution space of compression techniques and makes resulting recommendations.